预赛比赛计数比赛

问题描述：

我有一个preg match语句，它检查匹配项，但是我想知道如何计算匹配项.任何建议表示赞赏.

I have a preg match statement, and it checks for matches, but I was wondering how you can count the matches. Any advice appreciated.

$message='[tag] [tag]';
preg_match('/\[tag]\b/i',$message);

例如，此消息字符串的计数应导致2个匹配项

for example a count of this message string should lead to 2 matches

答

$message='[tag] [tag]';
echo preg_match_all('/\\[tag\\](?>\\s|$)/i', $message, $matches);

给出2.请注意，您不能使用\b，因为单词边界位于]之前，而不是之后.

gives 2. Note you cannot use \b because the word boundary is before the ], not after.